Apparatus for protection of converter modules

Abstract

A device ( 1 ) has a series circuit of submodules with a power semiconductor circuit and an energy accumulator connected in parallel with the power semiconductor circuit. Each submodule is associated with a short circuit device for shorting the submodule. The short circuit device is a vacuum switching tube. The device is cost-effective and at the same time enables safe bridging of a defective submodule.

1. A circuit configuration, comprising:
 a series circuit of a plurality of submodules each having a power semiconductor circuit and an energy storage device connected in parallel with said power semiconductor circuit; 
 each said submodule having a vacuum interrupter tube associated therewith, said vacuum interrupter tube forming a short-circuiting device for short-circuiting the respective said submodule; 
 a tripping and latching unit for latching said vacuum interrupter tube in a disconnected position with a latch and for removing said latch; and 
 said vacuum interrupter tube being configured to be moved, without a drive, from a disconnected position into a connected position, in which the respective said submodule is short-circuited, when said latch is removed, whereupon said vacuum interrupter tube is moved from the disconnected position into the connected position substantially only as a result of a pressure difference between an interior of said vacuum interrupter tube and an exterior atmosphere. 
 
     
     
       2. The circuit configuration according to  claim 1 , wherein said tripping and latching unit has a permanent magnet configured to produce a latching force, and a tripping means configured to counteract a holding force in order to release said latch. 
     
     
       3. The circuit configuration according to  claim 2 , wherein the tripping means is an electrical coil. 
     
     
       4. The circuit configuration according to  claim 1 , wherein said power semiconductor circuit is a full-bridge circuit. 
     
     
       5. The circuit configuration according to  claim 1 , wherein said power semiconductor circuit is a half-bridge circuit. 
     
     
       6. The circuit configuration according to  claim 1  configured as a converter with an AC voltage connection for connection of an AC voltage power supply system. 
     
     
       7. A circuit configuration, comprising:
 a multiplicity of submodules connected in series with one another, each of said submodules having a power semiconductor circuit and an energy storage device connected in parallel with said power semiconductor circuit; 
 a multiplicity of vacuum interrupter tubes each connected in parallel with a respective said submodule and each forming a short-circuiting device for short-circuiting the respective said submodule; 
 each said vacuum interrupter tube being movable from a disconnected position, in which the respective said submodule is active, into a connected position in which the respective said submodule is bypassed; 
 a tripping and latching unit for latching each said vacuum interrupter tube in a disconnected position with a latch and for removing said latch; and 
 wherein, when said latch is removed, said vacuum interrupter tube is moved from the disconnected position into the connected position substantially only as a result of a pressure difference between an interior of said vacuum interrupter tube and an exterior atmosphere.